Gear operating device



June 29, 1965 w. HOLZER 3,191,454

em OPERATING DEVICE Filed May 1, 1961 ,13 s :mnm12 I v m1]: 7

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9 m 15 I 16 7 F' 2. STATOR-1 14 lg 2 1 Q4 0- ROTOR 1 25 ARMATURE 1' f -zs 2 21 p21 Z2 INVENTOR WALTER HOLZER.

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Attorneys United States Patent Office I 3,191,454 Patented June 29, 1965 3,191,454 GEAR OPERATING DEVICE Walter Holzer, Drosteweg 19, Meersburg (Bodensee), Germany Filed May 1, 1961, Ser. No. 106,881 Claims priority, application Germany, May 17, 1960, H 39,449 4 Claims. (Cl. 74-472) This invention relates to a power transmission apparatus, and the invention has for its object to provide a transmission apparatus that can be used to give different speeds, or transmission ratios different directions of rotation of a driven member, or different torques, whilst employing only a simple actuating means. The invention is suitable for incorporation in a fully automat c washing machine or the like, but is not limited to this application.

The invention in its practical form obviates the need for complex switching arrangements, or cam operated switches, and their attendant expense, and in the case of apparatus using multiple contact arrangements, reduced reliability. The invention provides a system that can be electrically operated by means having simple contact arrangements.

In accordance with one feature of the invention, a change in a characteristic of a transmission system, such as speed, direction of rotation, or torque, is effected by a change in the excitation of an element of the system. A force produced electromagnetically in the drive system can be used, for example, to operate a sliding armature, operate a clutch or engage or disengage a gear drive; the change can be effected under the control of a single contact, which changes the excitation of the electromagnetic means.

A particularly advantageous form of the invention is one in which the electromagnetic means is an electric motor having an axially movable armature, which is made to move axially when the excitation of the motor is varied. The axial movement of the armature or shaft is employed to cause engagement of different members of a gear train connected to a common driven shaft, so to change speed, direction of rotation or torque to the driven shaft from, it may be, the motor Shaft.

In one embodiment, a driving pinion is moved, on movement of the armature to engage different gear wheels which effect reversal of the direction of rotation and, if required, a variation of torque; this change of the direction of rotation can be effected simply 'by opening or closing of a contact. The moving armature shaft may have a detent mechanism to hold the armature in a selected axial position corresponding to the excitation current whilst permitting the shaft to rotate.

The shaft can be spring biased to one limit of its travel and the detent mechanism arranged to hold the Shaft only against movement in the biased direction. The detent can be of the ratchet and pawl rotary. type. In the end position of the armature corresponding to maximum excitation current, when the armature is drawn fully into the magnetic field, it can be arranged that the detent is released by another impulse when the armature is returned by the biasing force to its initial position.

The magnetic circuit of the armature can have separate windings with different ampere-turns, to effect different extents of movement of the armature. With this arrangement the different windings can be provided by tappings, the different windings being selected as necessary. The magnetic circuit can also be constructed so as a to present a plurality of adjacent but separate circuits with air gaps of different sizes, this is equivalent to altering the ampere-turns and so controls the axial movement of the armature. Electrically, feeding the same excitation current to the windings associated with the different magnetic circuits is the same as feeding the same magnetic circuit with different excitation currents.

A simple and effective means of controlling the excitation current is by contacts arranged serially connected resistors.

Features and advantages of the invention will also appear from the following description of embodiments thereof in conjunction with the accompanying drawing, in which:

FIGURE 1 is a diagram of a transmission system including a motor with an axially movable armature, arranged to drive an output shaft in opposite directions of rotation;

FIGURE 2 is a corresponding diagram of a similar arrangement, affording different output speeds or output torques in response to axial movements of the armature, and

FIGURE 3 is a similar diagram of another embodiment having five different positions and with which five different speeds can be obtained, for example simply by operation of press-buttons.

In the arrangement shown in FIGURE 1 a motor includes a magnetic member field 1 with which is associated armature 2; the armature is suitably mounted so as to be axially movable. A driving pinion 3 is secured to the armature shaft; this pinion, according to the axial position of the armature shaft, can engage either a gear wheel 4 or a further gear wheel 5. Gear wheel 5 is fixed on a shaft on which is fixed also a gear wheel 6, which in turn meshes with a gear wheel 7 on shaft 8. Shaft 8 carries a pinion meshing with a gear wheel 12, driving output shaft 13. Gear wheel 4 is mounted on shaft 8.

When the motor is not energised, a spring 9 biases the armature into a position in which it is out of alignment with the field member 1, into the position shown; the bias is such that the armature is retained in this position, and pinion 3 retained in engagement with gear wheel 4, when the current fed to the motor windings is low, but sufficient to cause the motor to run and produce a useful output at shaft 13, in one direction.

If the current is increased, for example by switch contacts 11 short-circuiting a resistor 10 included in the supply to the motor, the armature moves in the direction of arrow 18, and pinion 3 is thereby disengaged from gear wheel 4 and engaged with gear wheel 5 so as to drive shaft 13 in the reverse direction.

FIGURE 2 shows an arrangement which is similar to that shown in FIGURE 1; in the two figures like parts bear like references. In this embodiment the armature shaft carries two pinions 14 and 15. When the current fed to the motor is at a low value, for example when contacts 11 are open, spring 9 moves pinion 14 into engagement with a gear wheel 16 on shaft 13. When the current is increased, for example when contacts 11 are closed, pinion 15 engages a second gear wheel 17 on shaft 13.

The gear ratios of 14, 16 and 15, 17 are chosen to be different, so that in the two axial positions of the armature the shaft 13 will run at different speeds.

With the arrangement of FIGURE 3, the shaft of the armature 2 is provided with a detent mechanism comprising a series of five truncated conical surfaces 29 and a spring biased cooperating pawl 30. This arrangement is so arranged that as the current to the motor is successively increased, the armature will move to and be retained in engagement with gear trains 33, 32, 31, 34, 35, affording different gear ratios to a common output shaft (not shown). The different motor currents and the different axial positions of the armature can be selected by means of series resistors 19, 20, 21, 22, 23, which can be shortor open-circuited by contacts 24, 25, 26, 27,

l 28 respectively. The means adopted for releasing the detent mechanism is shown schematically only but can be effected by a control current pulse as mentioned above; the armature will thereupon return to the position shown in FIGURE 3, under the action of spring 9.

Instead of the mechanical detent-mechanism described, the appropriate axial position of the armature can be secured by appropriate design of the armature, the co operating field structure, including the shaping of the structure and the disposition of multiple or tapped windings upon it the location is then obtained by primarily magnetic means.

The invention can be used with advantage in fully automatic washing means, making a single motor to becontrolled to give different speeds, direction of rotation or torque, by very simple means, but the invention can be Widely used where these features are advantageous.

I claim:

1. A driving and power transmission apparatus suitable for washing machines, comprising: an electromagnetic member for defining and providing a stator field; an armature rotating in said stator field, and being axially movable relative thereto, said electromagnetic member and said armature defining an electromot-or within an axially displaceable rotor; electric circuit means connected to said electromagnetic member for adjustably energizing said electromagnetic member; a shaft on said armature; spring means connected to said shaft for urging said armature in axial direction out of the magnetic field as being set up by said electromagnetic member upon energization thereof; a detent mechanism comprising a first member on said shaft and a second, stationarily positioned pawl for engaging said first member in one of a plurality of at least three positions so as to axially, positively arrest said shaft with said armature in one of said positions While permitting rotation of said shaft, each position being attainable upon a different adjustment of the energization of said electromagnetic member; a like plurality of gearing means selectively engageable with a gear on said shaft for being driven therefrom, depending upon the respective axial armature position; and means for releasing said pawl from engaging said first member.

2. A transmission according to claim 1, said electric circuit means comprising resistors connected in the supply circuit of said electromagnetic member, and contacts arranged to selectively short-circuit said resistors.

3. A driving and power transmission apparatus suitable for washing machines, comprising: an electromagnetic member forsetting up an electromagnetic stator field; an armature rotating in said stator field, and being axially movable relative thereto, said electromagnetic member and said armature defining an electromotor with an axially displaceable rotor; electric circuit means connected to said electromagnetic member for adjustably energizing said electromagnetic member; a shaft for said armature; spring means connected to said shaft for urging said armature in axial direction out of the magnetic field as being set up by said electromagnetic member upon energization thereof; a plurality of at least three truncated cones on said shaft defining a like plurality of axially directed engagement surfaces; a spring-biased pawl engaging any one of said surfaces for positively unidirectionally limiting axial movement of said armature and shaft while permitting rotation thereof, the respective surface to be engaged being determined by adjustment of the energization of said electromagnetic member; a like plurality of gearing means selectively engageable with a gear on said shaft for being driven therefrom, depending upon the respective axial armature position; and means for releasing said pawl from the respective surface it engages.

4. A driving and power transmission apparatus suitable for washing machines, comprising: a stator for an electromotor; electric circuit means for stepwise adjustably energizing said stator; an axially displaceable armature rotor in said motor; a shaft for said rotor; a plurality of detent means on said shaft defining a respective plurality of axial rotor positions; means for selectively and releasably engaging said detent means arresting said rotor in any of said axial positions but still permitting rotation thereof; a plurality of selectively, drivably engageable gearing means positioned corresponding to said axial rotor positions; and a gear wheel on said shaft rotating therewith and selectively engaging one of said gearing means for driving same in any of said axial positions.

References Cited by the Examiner UNITED STATES PATENTS 2,204,065 6/40 Beizer a- 310-409 2,311,168 2/43 Gendriess 310-209 2,345,778 4/44 Van Lammeren 3l0209 2,348,895 5/44 Gaudio 310-209 2,730,671 1/56 Von Ryan 310209 2,757,550 8/56 Weinfurt.

2,869,008 1/59 Carlson 310209 2,871,716 2/59 Stade. 7 3,001,099 9/61 Larkey 310-209 FOREIGN PATENTS 925,656 3/47 France.

DON A. WAITE, Primary Examiner.

MILTON O. HIRSHFIELD, Examiner. 

1. A DRIVING AND POWER TRANSMISSION APPARATUS SUITABLE FOR WASHING MACHINES, COMPRISING: AN ELECTROMAGNETIC MEMBER FOR DEFINING AND PROVIDING A STATOR FIELD; AN ARMATURE ROTATING IN SAID STATOR FIELD, AND BEING AXIALLY MOVABLE RELATIVE THERETO, SAID ELECTROMAGNETIC MEMBER AND SAID ARMATURE DEFINING AN ELECTROMOTOR WITHIN AN AXIALLY DISPLACEABLE ROTOR; ELECTRIC CIRCUIT MEANS CONNECTED TO SAID ELECTROMAGNETIC MEMBER FOR ADJUSTABLY ENERGIZING SAID ELECTROMAGNETIC MEMBER; A SHAFT ON SAID ARMATURE; SPRING MEANS CONNECTED TO SAID SHAFT FOR URGING SAID ARMATURE IN AXIAL DIRECTION OUT OF THE MAGNETIC FIELD AS BEING SET UP BY SAID ELECTROMAGNETIC MEMBER UPON ENERGIZATION THEREOF; A DETENT MECHANISM COMPRISING A 